20. PDF Viewing and Navigation

PDF support activates in v0.3.0 and uses the PDF.js display layer in a dedicated worker. Glitchpad supplies its own compact shell rather than embedding the generic PDF.js viewer.

The renderer provides virtualized page canvases, text selection, search, thumbnails, document outline and table-of-contents navigation, page labels, direct page navigation, zoom, rotation, internal links, metadata, and printing. Only visible and adjacent pages remain rendered; suspended tabs release canvases and retain compact navigation state.

PDF JavaScript, form submission, embedded-file launch, multimedia, remote resource access, automatic external-link opening, annotations editing, signatures, redaction, and document modification are disabled. Encrypted documents may request a password for in-memory use; passwords are never persisted or logged. Unsupported encryption produces a stable error.

The renderer accepts files through 512 MiB desktop and 256 MiB Android, at most 10,000 pages, and at most 200 MiB of active rendered surfaces desktop or 96 MiB Android. Ranged reads are used when the source supports seek. First content is the first requested page, not complete document parsing.